At matchpoints, north opened the bidding with one diamond. South could have prudently responded with an inverted minor raise, thinking notrump should play from partner's side if at all. Or he might have responded with a non-forcing 2NT. But he bashed directly to three notrump, optimistically trusting partner for any needed stoppers in the major suits. All then passed.
 
Against 3NT west led the ♥K, showing a very strong holding. East won the ace, but (que lastima!) had no heart to return.
 
East had 11 remaining cards, and on the return of any one of 10 of them, south would have happily diagnosed the reason for a non-heart return and simply planned to surrender a diamond trick to east while hearts languished. But our east found the only continuation to defeat the contract. East returned the ♠K.
 
Whether or not south ducked in dummy, three notrump could no longer be made. At the table, south let the queen hold the trick, but another spade established west's queen as a later entry. South ran his winners, but his attempts to pressure west or east fell a trick short. He could do no better than cash eight winners.
 
East's expert play was predicated on an assumption that the contract could be defeated, despite the blocked heart position. East could only hope that west's strong lead meant that hearts were ready to run.
 
East had believed that despite south's bid, there might be just enough unbid high card strength for west to have an honor card in addition to her long and strong hearts. If it was an unlikely ♣A, the contract would surely fail in any case. West might hold the ♣Q instead but if so a competent declarer would prevail by keeping the "danger hand" off lead, taking the club finesse through west and scoring 4 clubs, 4 diamonds and spade ace.
 
However, if west held the ♠Q, heroic action by east was needed. His possible sacrifice of a spade trick allowed him to "hand off" the spade entry to his partner before south could safely establish a 9th trick.

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